Problem: $ { \left[\begin{array}{rr}{0} & {2} \\ {0} & {-2}\end{array}\right]+\left[\begin{array}{rr}{1} & {0} \\ {3} & {4}\end{array}\right] = {?} } $
Answer: To find the sum of two matrices, add the corresponding items between each matrix. ${\left[\begin{array}{rr}{0}+{1} & {2}+{0} \\ {0}+{3} & {-2}+{4}\end{array}\right]}$ Now, simplify: ${\left[\begin{array}{rr}{1} & {2} \\ {3} & {2}\end{array}\right]}$